1. Field of the Invention
The present invention relates to a battery charging pad that transmits power by magnetic induction to charge rechargeable batteries contained in a device housing a battery that is placed on the charging pad.
2. Description of the Related Art
A battery charging pad (charging stand, charging cradle) has been developed to charge a battery housed in a device by transmitting power from a transmitting coil (power supply coil, primary coil) to a receiving coil (induction coil, secondary coil) by magnetic induction. (Refer to Japanese Laid-Open Patent Publication H09-63655 (1997) and Utility Model Registration No. 3011829.)
JP H09-63655 A cites a configuration with a charging pad housing a transmitting coil driven by an alternating current (AC) power source, and a device housing a battery containing a receiving coil that magnetically couples with the transmitting coil. By positioning the transmitting coil in close proximity to the receiving coil, this charging pad can charge the battery housed in a device without direct physical contact.